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This work presents mathematical modelling of moist air condensation process in a fuel cell turbine. A condensation model based on the classical nucleation theory and the Hertz–Knudsen droplet growth model is established. The numerical approach is validated through experimental results of the MS nozzle and a fuel cell turbine, and the simulation fits the experimental data well. Influences of inlet temperature and pressure on condensation process in the turbine is examined. Results show that increase of inlet temperature apparently weakens condensation and inlet heating can be realized by arranging a gas-to-gas heat exchanger in the air supply subsystem without consuming additional energy. Moreover, at the same mass flow rate increase of inlet pressure reduces the expansion ratio, thereby curbing the condensation. Compared with the matching scheme of a bypass valve, turbocharger matching with a back-pressure valve allows higher inlet pressure to be achieved and can effectively suppress the condensation. • An electric turbocharger for 100 kW PEMFC system is designed, manufactured and evaluated. • A numerical model on condensation occurring in turbine is established. • Inflow heating is beneficial to suppressing the condensation. • Adding back-pressure valves to the turbine can help diminish the condensation. [ABSTRACT FROM AUTHOR]

Thirteen compounds, including coumarins (1 − 4), phenols (5 − 10) and others (11 − 13), were isolated from the stems of Ostodes paniculata Bl. Their structures were elucidated by NMR, MS analyses and comparison with literature data. Compounds (1 − 2 , 4 − 13) were isolated from the Ostodes genus for the first time. The chemotaxonomical significance of the isolated compounds was also discussed, based on the chemical constituents from some plants of Trib. Cluytieae Pax (Euphorbiaceae). • Twelve compounds were first isolated from the genus Ostodes (Euphorbiaceae). • The chemotaxonomic significance of the isolated compounds was described. • Chemical taxonomy can prove morphology classification scientific. [ABSTRACT FROM AUTHOR]

The underground powerhouse of Lianghekou hydropower station is deeply buried with high ground stress and complicated geological conditions. To delineate rock mass damage zones and analyze the stability of underground powerhouse subjected to excavation disturbance, an ESG monitoring system was applied to carry out real-time monitoring against the inner micro-fracture activity of surrounding rock mass. In order to solve the problem that the deformation of surrounding rock mass cannot be monitored due to the failure of multipoint displacement meters, the engineering analogy method is adopted to forecast the deformation of surrounding rock mass by comparing the similar projects of Houziyan and Baihetan hydropower stations. Research results show: (1) The failure of surrounding rock mass was stress-driven failure, and was primarily characterized by a medium degree of stress-induced failure. (2) During the monitoring period, microseismic (MS) events clustering area formed, which was both related to blasting excavation disturbance of the bus tunnel and the formed crossed free surfaces. (3) The seismic source parameters during the deformation of surrounding rock mass in similar projects were analyzed, and the variation characteristics of the frequency, energy, b -value, central frequency, apparent stress, and apparent volume of MS events were summarized. (4) The engineering analogy method was adopted to forecast that the deformation period of surrounding rock mass of Lianghekou hydropower station is from April 25 to May 2, 2016. The present achievements can provide some references for similar deep underground excavation engineering. [ABSTRACT FROM AUTHOR]

• An electric turbocharger is developed for a 100 kW PEMFC system. • Performances of the developed turbine is investigated experimentally. • Changes of nozzle vane angle affects condensation in the rotor area. • Low wall temperature enhances condensation inside the turbine. A turbine with variable geometry can fully recover energy from the fuel cell exhaust gas and effectively reduce parasitic power consumption of the compressor. In this study, an electric turbocharger is developed for a 100 kW fuel cell system. To investigate condensation occurring inside the turbine, a wet air condensation model based on a classical nucleation theory and the Hertz-Knudsen droplet model is proposed. Validation of the model is made by testing aerodynamic performances of the turbine. In order to do this, an air humidification bench is built and exhaust gas from the fuel cell cathode outlet is replaced by humidified high-pressure air. Numerical simulation and experiment results are in good agreement. Influences of nozzle vane angle and wall temperature of the turbine on its aerodynamic performances are examined. Results show that when the nozzle opening turns small, flow capacity of the turbine decreases, pressure at the nozzle outlet declines, and condensation is more likely to occur in the rotor area. As the wall temperature drops, area in which water vapor condenses rapidly moves forward from the rotor to the nozzle. Liquid water mass fraction at different locations increases approximately 5 % as the wall temperature decreases from 310 K to 290 K. [ABSTRACT FROM AUTHOR]

A kinematics analysis of a new hybrid mechanical leg suitable for bipedal robots was carried out and the gait of the robot walking on flat ground was planned. Firstly, the kinematics of the hybrid mechanical leg were analyzed and the applicable relevant models were established. Secondly, based on the preliminary motion requirements, the inverted pendulum model was used to divide the robot walking into three stages for gait planning: mid-step, start and stop. In the three stages of robot walking, the forward and lateral robot centroid motion trajectories and the swinging leg joint trajectories were calculated. Finally, dynamic simulation software was used to simulate the virtual prototype of the robot, achieving its stable walking on flat ground in the virtual environment, and verifying the feasibility of the mechanism design and gait planning. This study provides a reference for the gait planning of hybrid mechanical legged bipedal robots and lays the foundation for further research on the robots involved in this thesis. [ABSTRACT FROM AUTHOR]

AbstractMany mutations in the human rhodopsin gene (RHO) cause autosomal dominant retinitis pigmentosa (ADRP). Our previous studies with a P23H (proline-23 substituted by histidine) RHOtransgenic mouse model of ADRP demonstrated significant improvement of retinal function and preservation of retinal structure after transfer of wild-type rhodopsin by AAV. In this study we demonstrate long-term rescue of retinal structure and function by a single virus expressing both RHOreplacement cDNA and small interfering RNA (siRNA) to digest mouse Rhoand human P23H RHOmRNA. This combination should prevent overexpression of rhodopsin, which can be deleterious to photoreceptors. On the basis of the electroretinogram (ERG) response, degeneration of retinal function was arrested at 2 months postinjection, and the response was maintained at this level until termination at 9 months. Preservation of the ERG response in P23H RHOmice reflected survival of photoreceptors: both the outer nuclear layer (ONL) and outer segments of photoreceptor cells maintained the same thickness as in nontransgenic mice, whereas the control injected P23H eyes exhibited severe thinning of the ONL and outer segments. These findings suggest that delivery of both a modified cDNA and an siRNA by a single adeno-associated viral vector provided long-term rescue of ADRP in this model. Because the siRNA targets human as well as mouse rhodopsin mRNAs, the combination vector may be useful for the treatment of human disease. [ABSTRACT FROM AUTHOR]

Abstract: Exposure to pesticides has been speculated to contribute to the development of sporadic Parkinson''s disease (PD) characterized by a progressive degeneration of the nigrostriatal dopaminergic pathway. Activation of brain microglia that produce various neurotoxic factors including cytokines and reactive oxygen species (ROS) has been increasingly associated with dopaminergic neurodegeneration induced by various toxicants. Dieldrin, a highly persistent organochlorinated pesticide found enriched in the substantia nigra of some postmortem PD brains, has been shown to be toxic to dopamine neurons. In this study, we set out to determine the effect of dieldrin on the production of ROS and the underlying mechanism of action in murine microglia. Treatment of microglial cells with 0.1 nM to 1 μM dieldrin for 24 h resulted in a concentration-dependent generation of ROS. The dieldrin-induced microglial ROS generation was time-dependent in that significant ROS production was observed in cells 12–24 h, but not 6 h after dieldrin treatment. Furthermore, the dieldrin-induced microglial ROS generation was significantly reduced by inhibitors of NADPH oxidase, gene transcription and protein synthesis. In addition to immortalized microglial cells, dieldrin induced a concentration-dependent ROS generation in primary microglia, but not in primary astroglia. These results demonstrate that nanomolar concentrations of dieldrin can stimulate microglia to produce ROS that may contribute to the degeneration of dopamine neurons known to be vulnerable to oxidative damage. These findings provide important information on the potential role of microglia in dieldrin-induced neurodegeneration in relevance to the development of idiopathic PD. [Copyright &y& Elsevier]

A group of phenanthrene derivatives with different deformed types, including four previously undescribed derivatives (1 – 4), an undescribed natural product (5) and five known compounds (6 – 10), were isolated from the leaves and stems of Strophioblachia fimbricalyx by molecular networking based on UPLC-MS/MS method. Their structures were established by 1D/2D NMR spectroscopy, HRESIMS, quantum chemistry calculation, and single crystal X-ray diffraction. In biogenic pathways, series of deformed phenanthrenes were all suspected to be derived from 6/6/6 tricyclic phenanthrenes with a gem-dimethyl unit in one ring as characteristic components of Strophioblachia. Fimbricalyxone (1) and trigoxyphin M (6) with a 6/6/5 tricyclic carbon skeleton were reported for the first time from the genus and fimbricalyxanhydride C (2) is the first example of anhydride type bearing a rare 8,9-oxycycle. All the isolates were evaluated for their cytotoxic activity against three tumor cell lines, and compounds 8 and 10 exhibited significant activity with IC 50 values of 4.65–9.02 μM, and the structure–activity relationship of the deformed phenanthrenes was discussed. In addition, the X-ray structure of 8 and 10 and the antineoplastic activity of 10 are reported herein for the first time. Trigohowilol G (10) inhibiting the proliferation of A549 cells might be related to cell cycle distribution and the induction of S phase arrest, and it induced cell apoptosis through Bad/Bax/Cleaved PARP1 pathway. [Display omitted] • Structurally diverse phenanthrenes were obtained from Strophioblachia fimbricalyx. • They were all derived from 6/6/6 tricyclic phenanthrenes in biogenic pathways. • Trigohowilol G (10) showed stronger cytotoxic activities by inducing cell apoptosis. [ABSTRACT FROM AUTHOR]

• A comprehensive multi-parameter monitoring system was established. • Coupled analysis of the characteristics of deformation, stress, and MS events during the WIZ collapse process. • Identified the deformation and damage analysis of underground caverns with WIZ. The stability of surrounding rock is deteriorated due to the characteristics of Weak Interlayer Zone (WIZ) in underground caverns. To address the deformation and small-scale collapse issues during the construction of a hydropower station's underground caverns, this study combined on-site investigations with theoretical analyses. A comprehensive multi-parameter monitoring system was established, including microseismic monitoring, multi-point extensometers, bolt stress meters, and borehole television, to elucidate the deformation characteristics and damage of the weak interlayer zone. First, the distribution characteristics of multi-parameter of WIZ in tailrace surge chamber during small-scale collapse were analyzed. The internal relationship between this multi-parameter and the WIZ instability process was discussed. Second, fracture characteristics, microseismic source characteristics, and local stress of the rock mass during deformation and failure of WIZ were presented based on moment tensor inversion. Then, the correlation between multi-parameter before and after WIZ collapse was investigated through coupling analysis. Finally, the failure mode of the rock mass within the WIZ range was determined, and the deformation characteristics of WIZ were explored. The research results can provide some references for understanding surrounding rock mass damage and failure mechanisms in underground caverns with WIZ. It can also guide the design and optimization of excavation and support systems for similar projects. [ABSTRACT FROM AUTHOR]

Coriolus versicolor is an edible medicinal mushroom in China. Two polysaccharides, named as CVPn and CVPa were separated from the dried fruiting bodies of Coriolus versicolor by water extraction and ethanol precipitation. Their chemical structures were well elucidated with overall consideration of monosaccharide composition, methylation analysis and 1D/2D-NMR spectra data. The bioactivities on RAW 264.7 macrophages cells were evaluated, and further structure-bioactivity relationships were concluded. With molecular weight of 29.7 kDa for CVPn and 50.8 kDa for CVPa, the two isolated polysaccharides were both composed of (l → 4)-β-/(1 → 3)-β- d -glucopyranosyl group as backbone with branches attached at O-6 site. Comparing to CVPn, CVPa with relative high molecular weight and less branches showed significant induction of NO production, obvious augmentation of iNOS and TNF-α mRNA expression level, and phagocytosis on RAW 264.7 cells. These results clarified that CVP polysaccharides with less branches and high molecular weight possessed enhanced immunomodulatory ability, and this finding could be a reference for the utilization of Coriolus versicolor. • Two polysaccharides with Mw of 29.7 and 50.8 kDa were firstly and fully elucidated. • CVPn and CVPa were composed of (l → 4)-β-/(1 → 3)-β- d -glucopyranosyl group as backbone. • CVPa had significant bioactivities on RAW 264.7 vis-à-vis CVPn. [ABSTRACT FROM AUTHOR]

The present work was undertaken to investigate chemical constituents and chemotaxonomic significance from Strophioblachia fimbricalyx. As a result, thirteen phenylpropanoids were isolated, including six lignans (1 − 6), four coumarins (7 − 10) and three phenylpropanoid glycosides (11 − 13). Their structures were identified by spectroscopic analyses and comparison with literature data. The lignans presented different structural types, such as benzofuran, furofuran, biphenyl and hybrid lignans, which were first reported from the genus Strophioblachia. This work expanded the knowledge of the chemical diversity of the genus, and the chemotaxonomic significance of these phenylpropanoids was discussed herein. • Thirteen phenylpropanoids were isolated from Strophioblachia fimbricalyx for the first time. • The lignans with different structural types were first reported from the Strophioblachia genus. • The chemotaxonomic significance of these phenylpropanoids was discussed. [ABSTRACT FROM AUTHOR]

In recent years, significant progress has been made in employing reinforcement learning for controlling legged robots. However, a major challenge arises with quadruped robots due to their continuous states and vast action space, making optimal control using simple reinforcement learning controllers particularly challenging. This paper introduces a hierarchical reinforcement learning framework based on the Deep Deterministic Policy Gradient (DDPG) algorithm to achieve optimal motion control for quadruped robots. The framework consists of a high-level planner responsible for generating ideal motion parameters, a low-level controller using model predictive control (MPC), and a trajectory generator. The agents within the high-level planner are trained to provide the ideal motion parameters for the low-level controller. The low-level controller uses MPC and PD controllers to generate the foot-end force and calculates the joint motor torque through inverse kinematics. The simulation results show that the motion performance of the trained hierarchical framework is superior to that obtained using only the DDPG method. [ABSTRACT FROM AUTHOR]

SP 1 sp H and SP 13 sp C NMR spectra were published [[18]]. SP 1 sp H NMR (400 MHz, CDCl SB 3 sb , , ppm, J/Hz): 0.88 (3H, t, J = 6.6, H-16'), 1.61 (2H, m, H-3'), 2.35 (2H, t, J = 7.6, H-2'), 3.47 (1H, s, OH), 3.57 (1H, dd, J = 11.6, 4.2, H-3a), 3.66 (1H, dd, J = 11.6, 4.8, H-3b), 3.91 (1H, m, H-2), 4.18 (1H, dd, J = 12.0, 3.2, H-1a), 4.14 (1H, dd, J = 12.0, 6.4, H-1b). These structures of B 1-17 b were all elucidated using spectroscopic methods, including SP 1 sp H NMR, SP 13 sp C NMR, and MS techniques. SP 1 sp H NMR (600 MHz, CDCl SB 3 sb , , ppm, J/Hz): 1.30 (3H, s, H-11), 1.49 (3H, s, H-10), 1.54 (1H, d, J = 14.4, H-2 ), 1.75 (1H, d, J = 4.8, H-4 ), 1.78 (3H, s, H-9), 2.00 (1H, dd, J = 15.0, H-2 ), 2.43 (1H, dd, J = 13.2, H-4 ), 4.24 (1H, m, H-3), 5.77 (1H, s, H-7). [Extracted from the article]

Abstract: Oxidative stress in the retinal pigment epithelium (RPE) is hypothesized to be a major contributor to the development of age-related macular degeneration (AMD). Mitochondrial manganese superoxide dismutase (MnSOD) is a critical antioxidant protein that scavenges the highly reactive superoxide radical. We speculated that specific reduction of MnSOD in the RPE will increase the level of reactive oxygen species in the retina/RPE/choroid complex leading to pathogenesis similar to geographic atrophy. To test this hypothesis, an Sod2-specific hammerhead ribozyme (Rz), delivered by AAV2/1 and driven by the human VMD2 promoter was injected subretinally into C57BL/6J mice. Dark-adapted full field electroretinogram (ERG) detected a decrease in the response to light. We investigated the age-dependent phenotypic and morphological changes of the outer retina using digital fundus imaging and SD-OCT measurement of ONL thickness. Fundus microscopy revealed pigmentary abnormalities in the retina and these corresponded to sub-retinal and sub-RPE deposits seen in SD-OCT B-scans. Light and electron microscopy documented the localization of apical deposits and thickening of the RPE. In RPE flat-mounts we observed abnormally displaced nuclei and regions of apparent fibrosis in the central retina of the oldest mice. This region was surrounded by enlarged and irregular RPE cells that have been observed in eyes donated by AMD patients and in other mouse models of AMD. [Copyright &y& Elsevier]

N -glycosylation has been revealed to be tightly associated with cancer metastasis. As a key transferase that catalyzes the formation of β1,4 N -acetylglucosamine (β1,4GlcNAc) branches on the mannose core of N -glycans, N -acetylglucosaminyltransferase IVa (GnT-IVa) has been reported to be involved in hepatocellular carcinoma (HCC) metastasis by forming N -glycans; however, the underlying mechanisms are largely unknown. In the current study, we found that GnT-IVa was upregulated in HCC tissues and positively correlated with worse outcomes in HCC patients. We found that GnT-IVa could promote tumor growth in mice; notably, this effect was attenuated after mutating the enzymatic site (D445A) of GnT-IVa, suggesting that GnT-IVa regulated HCC progression by forming β1,4GlcNAc branches. To mechanistically investigate the role of GnT-IVa in HCC, we conducted GSEA and GO functional analysis as well as in vitro experiments. The results showed that GnT-IVa could enhance HCC cell migration, invasion and adhesion ability and increase β1,4GlcNAc branch glycans on integrin β1 (ITGB1), a tumor-associated glycoprotein that is closely involved in cell motility by interacting with vimentin. Interruption of β1,4GlcNAc branch glycan modification on ITGB1 could suppress the interaction of ITGB1 with vimentin and inhibit cell motility. These results revealed that GnT-IVa could promote HCC cell motility by affecting the biological functions of ITGB1 through N -glycosylation. In summary, our results revealed that GnT-IVa is highly expressed in HCC and can form β1,4GlcNAc branches on ITGB1, which are essential for interactions with vimentin to promote HCC cell motility. These findings not only proposed a novel mechanism for GnT-IVa in HCC progression but also revealed the significance of N -glycosylation on ITGB1 during the process, which may provide a novel target for future HCC therapy. • GnT-IVa enhances cell motility and correlates with poor outcomes of HCC. • GnT-IVa increases β1,4GlcNAc branches on ITGB1 to promote cell motility of HCC. • β1,4GlcNAc branches on ITGB1 affect interactions with vimentin in HCC. [ABSTRACT FROM AUTHOR]

Chronic oxidative stress contributes to age related diseases including age related macular degeneration (AMD). Earlier work showed that the 5-hydroxy-tryptamine 1a (5HT1a) receptor agonist 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT) protects retinal pigment epithelium (RPE) cells from hydrogen peroxide treatment and mouse retinas from oxidative insults including light injury. In our current experiments, RPE derived cells subjected to mitochondrial oxidative stress were protected from cell death by the up-regulation of anti-oxidant enzymes and of the metal ion chaperone metallothionein. Differentiated RPE cells were resistant to oxidative stress, and the expression of genes for protective proteins was highly increased by oxidative stress plus drug treatment. In mice treated with 8-OH-DPAT, the same genes ( MT1, HO1, NqO1, Cat, Sod1 ) were induced in the neural retina, but the drug did not affect the expression of Sod2 , the gene for manganese superoxide dismutase. We used a mouse strain deleted for Sod2 in the RPE to accelerate age-related oxidative stress in the retina and to test the impact of 8-OH-DPAT on the photoreceptor and RPE degeneration developed in these mice. Treatment of mice with daily injections of the drug led to increased electroretinogram (ERG) amplitudes in dark-adapted mice and to a slight improvement in visual acuity. Most strikingly, in mice treated with a high dose of the drug (5 mg/kg) the structure of the RPE and Bruch's membrane and the normal architecture of photoreceptor outer segments were preserved. These results suggest that systemic treatment with this class of drugs may be useful in preventing geographic atrophy, the advanced form of dry AMD, which is characterized by RPE degeneration. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration (AMD), a major cause of blindness in the elderly, is associated with oxidative stress, lipofuscin accumulation and retinal degeneration. The aim of this study was to determine if a 5-HT1A receptor agonist can reduce lipofuscin accumulation, reduce oxidative damage and prevent retinal cell loss both in vitro and in vivo. Autophagyderived and photoreceptor outer segment (POS)-derived lipofuscin formation was assessed using FACS analysis and confocal microscopy in cultured retinal pigment epithelial (RPE) cells in the presence or absence of the 5-HT1A receptor agonist, 8-OH DPAT. 8-OH DPAT treatment resulted in a dose-dependent reduction in both autophagy- and POS-derived lipofuscin compared to control. Reduction in autophagy-induced lipofuscin was sustained for 4 weeks following removal of the drug. The ability of 8-OH DPAT to reduce oxidative damage following exposure to 200 μM H2O2 was assessed. 8-OH DPAT reduced superoxide generation and increased mitochondrial superoxide dismutase (MnSOD) levels and the ratio of reduced glutathione to the oxidized form of glutathione in H2O2-treated cells compared to controls and protected against H2O2-initiated lipid peroxidation, nitrotyrosine levels and mitochondrial damage. SOD2 knockdown mice, which have an AMD-like phenotype, received daily subcutaneous injections of either saline, 0.5 or 5.0 mg/kg 8-OH DPAT and were evaluated at monthly intervals. Systemic administration of 8-OH DPAT improved the electroretinogram response in SOD2 knockdown eyes of mice compared to knockdown eyes receiving vehicle control. There was a significant increase in the ONL thickness in mice treated with 8-OH DPAT at 4 months past the time of MnSOD knockdown compared to untreated controls together with a 60% reduction in RPE lipofuscin. The data indicate that 5-HT1A agonists can reduce lipofuscin accumulation and protect the retina from oxidative damage and mitochondrial dysfunction. 5-HT1A receptor agonists may have potential as therapeutic agents in the treatment of retinal degenerative diseas. [ABSTRACT FROM AUTHOR]